'''
You are given an array with positive numbers and a number N.
You should find the N-th power of the element in the array with the index N.
If N is outside of the array, then return -1.
Don't forget that the first element has the index 0.
'''

def index_power(array, n):
    """
        Find Nth power of the element with index N.
    """
    # in python 0**0 = 1
    try:
        return array[n]**n
    except IndexError:
        return -1

if __name__ == '__main__':
    #These "asserts" using only for self-checking and not necessary for auto-testing
    assert index_power([1, 2, 3, 4], 2) == 9, "Square"
    assert index_power([1, 3, 10, 100], 3) == 1000000, "Cube"
    assert index_power([0, 1], 0) == 1, "Zero power"
    assert index_power([1, 2], 3) == -1, "IndexError"
    print("Coding complete? Click 'Check' to review your tests and earn cool rewards!")
